Tea rolling dynamic regulation and control system based on multi-parameter coupling optimization

Abstract

The invention relates to the technical field of tea treatment before extraction, and provides a multi-parameter coupling optimization-based dynamic regulation and control system for tea rolling, which comprises a percolate conductivity detection module, a cell disruption rate identification module, a multi-parameter coupling optimization module and a self-adaptive regulation and control execution module, the exudate conductivity detection module detects the conductivity of the tea exudate in the rolling process in real time; the cell breakage rate identification module identifies the cell breakage rate of the current tea based on the conductivity value detected by the percolate conductivity detection module; the multi-parameter coupling optimization module generates optimized rolling control parameters on the basis of the breakage rate identified by the cell breakage rate identification module in combination with the temperature and the moisture content of the tea leaves; and the adaptive regulation and control execution module receives the control parameters generated by the multi-parameter coupling optimization module and adaptively regulates the actual working parameters of the rolling machine.

Description

Technical Field

[0001] This invention relates to the field of tea processing technology before extraction, and in particular to a dynamic control system for tea rolling based on multi-parameter coupling optimization. Background Technology

[0002] In the initial processing of tea, rolling is a crucial step in shaping tea quality. Its purpose is to break down the tea's cell structure through mechanical force, promote the release of tea juice, and tightly roll the tea leaves into strips. The quality of rolling directly affects the tea's appearance, internal quality, and the efficiency of its dissolved components during brewing. However, due to batch-to-batch variations in the tenderness, moisture content, and structure of tea raw materials, improper setting of process parameters such as rolling pressure, time, and speed can easily lead to insufficient cell damage (under-rolling) or excessive damage (over-rolling), resulting in problems such as low tea strip yield, high broken tea rate, and unstable quality. Existing tea rolling equipment mainly relies on manual experience to set process parameters or uses simple pressure-time program control, but it is difficult to achieve real-time monitoring and dynamic response control of the tea cell damage state during rolling.

[0003] For example, Chinese patent CN204930234U discloses a self-controlled tea rolling machine, which controls various components through a control system. First, an initial capping pressure and rolling drum speed are set based on the age and moisture content of the tea leaves. The pressure detected by the pressure sensor is compared with the set pressure in real time, and the signal is fed back to the pressurizing and driving mechanisms to control the pressure and speed, thus achieving closed-loop control of pressure and speed. While this solution can set corresponding initial process parameters based on the initial state of the tea leaves and achieve closed-loop pressure control during rolling, it relies solely on pressure values ​​as the control basis. This fails to directly reflect the essential goal of rolling—the degree of cell damage—and does not establish a quantitative relationship between cell damage rate and exudate characteristics. Therefore, it cannot precisely adjust the machine based on the actual damage state of the tea leaves.

[0004] Another Chinese patent, CN207604467U, discloses a tea rolling machine, including a lotus-shaped base and a rolling drum. The rolling drum, driven by a transmission structure, moves in a circular motion on the lotus-shaped base. A fan is connected to the bottom of a fixed plate, blowing air through its outlet to sweep the tea leaves between adjacent lotus leaves, thus solving the problem of tea leaves scattered between the lotus leaves and not being fully rolled. While this device improves the uniformity of tea rolling to some extent, its control method is still a fixed program control, lacking the ability to perceive real-time changes in the state of the tea leaves during rolling. It also does not consider the differences in breakage rates caused by uneven pressure on different tea layers, and cannot achieve layered monitoring and differentiated control.

[0005] In addition, US Patent 980213A discloses a tea-leaf-rolling machine that uses propeller-shaped blades rotating at the bottom of a container. The blade surfaces tilt downwards in the direction of rotation, applying a combined action of lifting, falling, squeezing, and rolling to the tea leaves. This device optimizes the rolling action through mechanical structural innovation, but its control system is relatively simple, only able to adjust the rotation speed and basic pressure. It does not involve quantitative detection of the degree of rolling, nor does it have a mechanism for coupled control based on key parameters such as tea temperature and moisture content.

[0006] In addition, the existing technology has the following defects: 1. The kneading equipment can only monitor physical process parameters such as pressure, speed and temperature, and cannot directly detect the essential indicator of kneading - cell damage rate, resulting in a disconnect between control target and quality target; 2. Traditional devices lack the ability to analyze the characteristics of exudate (such as conductivity, flow rate and refractive index) online, and cannot calculate the degree of cell damage through the electrochemical characteristics of exudate, making it difficult to achieve closed-loop feedback control based on damage rate; 3. Existing equipment does not consider the force difference of tea leaves at different depths in the kneading barrel, and cannot achieve layered damage rate monitoring and uniformity assessment, resulting in the common phenomenon of under-kneading of upper tea leaves and over-kneading of lower tea leaves; 4. Traditional control methods neglect the significant impact of temperature and moisture content on cell wall toughness, and fail to establish a multi-parameter coupled optimization model of "temperature-moisture content-pressure," making it impossible to dynamically adjust rolling parameters based on the physiological state of tea leaves; 5. Existing rolling machines mostly use fixed circular motion trajectories, lacking the ability to adaptively switch to elliptical or eccentric circular trajectories based on the breakage uniformity coefficient, making it difficult to solve the problem of localized over-rolling caused by uneven tea leaf distribution; 6. In tea rolling application scenarios, there is still a lack of intelligent rolling systems that can simultaneously achieve online analysis of multiple exudate parameters, inversion calculation of layered breakage rate, coupled optimization of temperature-moisture content-pressure, adaptive control of rolling trajectory, and segmented target control.

[0007] This invention addresses common problems in the field, such as the inability to directly detect cell damage rate, the lack of utilization of exudate characteristics, the absence of stratified monitoring, the lack of multi-parameter coupling control, the fixed and singular kneading trajectory, and poor quality consistency. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of current systems by proposing a dynamic control system for tea rolling based on multi-parameter coupling optimization.

[0009] To overcome the shortcomings of the prior art, the present invention adopts the following technical solution:

[0010] A dynamic control system for tea rolling based on multi-parameter coupling optimization includes an exudate conductivity detection module, a cell disruption rate identification module, a multi-parameter coupling optimization module, and an adaptive control execution module. The exudate conductivity detection module detects the conductivity of the tea exudate in real time during the rolling process.

[0011] The cell breakage rate identification module identifies the current cell breakage rate of the tea leaves based on the conductivity value detected by the exudate conductivity detection module; the multi-parameter coupling optimization module generates optimized kneading control parameters based on the breakage rate identified by the cell breakage rate identification module, combined with the tea leaf temperature and moisture content; the adaptive control execution module receives the control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the actual working parameters of the kneading machine.

[0012] The multi-parameter coupling optimization module includes a breakage rate deviation calculation unit, a temperature correction unit, a moisture content correction unit, and a coupling calculation unit. The breakage rate deviation calculation unit calculates the deviation between the current cell breakage rate identified by the cell breakage rate identification module and the preset target breakage rate. The temperature correction unit generates a temperature correction parameter based on the current tea temperature. The moisture content correction unit generates a moisture content correction parameter based on the current tea moisture content. The coupling calculation unit generates rolling control parameters based on the deviation value calculated by the breakage rate deviation calculation unit, the temperature correction parameter generated by the temperature correction unit, and the moisture content correction parameter generated by the moisture content correction unit.

[0013] Optionally, the exudate conductivity detection module includes a layered detection structure, which divides the collection space at the bottom of the kneading disc into multiple independent collection areas along the radial direction. Each area is provided with an independent exudate collection channel and conductivity detection unit.

[0014] Optionally, the layered detection structure divides the bottom of the kneading disc radially from the center outward into three independent collection areas: a central area, a middle area, and an edge area.

[0015] Optionally, the cell damage rate identification module identifies the damage rate by establishing a quantitative mapping relationship between the exudate conductivity and the cell damage rate, and calculates the difference between the measured conductivity and the benchmark conductivity calibrated before kneading. Combined with a preset conductivity-damage rate conversion coefficient, the cell damage rate of the current tea leaves is obtained by inversion.

[0016] Optionally, the adaptive control execution module includes a pressure adjustment unit, which receives the kneading pressure control parameters generated by the multi-parameter coupling optimization module, and adaptively adjusts the pressure device of the kneading machine to change the kneading pressure applied to the tea leaves.

[0017] Optionally, the temperature correction parameter is determined in segments according to the tea temperature range: when the tea temperature is within the first temperature range, it is determined as the first correction coefficient; when the tea temperature is below the first temperature range, it is determined as the second correction coefficient, which is less than the first correction coefficient, to reduce the kneading pressure; and when the tea temperature is above the first temperature range, it is determined as the third correction coefficient, which is greater than the first correction coefficient, to increase the kneading pressure.

[0018] Optionally, the coupling calculation unit generates the kneading control parameters in the following manner: the preset reference kneading pressure is coupled with the temperature correction parameter in a first coupling operation, and then coupled with the moisture content correction parameter in a second coupling operation to obtain the corrected reference pressure. Then, the corrected reference pressure is adjusted by the deviation value calculated by the breakage rate deviation calculation unit to generate a real-time kneading pressure control value as the kneading control parameter.

[0019] Optionally, the moisture content correction parameter is determined in segments according to the moisture content range of the tea leaves: when the moisture content of the tea leaves is within the first moisture content range, it is determined as the first correction coefficient; when the moisture content of the tea leaves is below the first moisture content range, it is determined as the second correction coefficient, which is less than the first correction coefficient, in order to reduce the rolling pressure and prevent excessive damage to the tea leaves; when the moisture content of the tea leaves is above the first moisture content range, it is determined as the third correction coefficient, which is greater than the first correction coefficient, in order to increase the rolling pressure and overcome the problem of cells not being easily damaged due to high moisture content.

[0020] The beneficial effects achieved by this invention are:

[0021] 1. By combining the layered detection structure of the exudate conductivity detection module with the data collection of conductivity at different radial positions (center, middle, and edge) of the kneading disc, and the weighted average calculation of the overall breakage rate by the cell damage rate identification module, the system can identify the differences in tea breakage at different locations within the kneading space, obtain spatial distribution information, and ensure that the entire system has the ability to comprehensively perceive the state of the kneading space and improve the accuracy of breakage rate identification.

[0022] 2. By combining the conductivity sensor of the exudate conductivity detection module to measure the conductivity of the exudate with the conductivity-damage rate inversion algorithm of the cell damage rate identification module, the system fully utilizes the electrochemical properties of the exudate as a characterization parameter of the degree of damage. This transforms the previously neglected or directly discharged exudate into a key detection target, ensuring that the entire system has the advantages of multi-dimensional information acquisition and high-sensitivity detection.

[0023] 3. By combining the real-time acquisition of exudate conductivity data by the exudate conductivity detection module with the establishment of a quantitative mapping relationship between conductivity and damage rate by the cell damage rate identification module, the system can convert changes in electrolyte ion concentration in the exudate into cell damage rate values ​​in real time. This enables the online direct detection of cell damage rate, an essential indicator of the kneading process, solving the problem that cell damage rate cannot be directly measured in existing technologies and can only rely on experience or post-process detection. This ensures that the entire system has the ability to control based on essential process parameters.

[0024] 4. Through the multi-parameter coupling optimization module, rolling control parameters are dynamically generated based on real-time breakage rate deviation, temperature correction parameters, and moisture content correction parameters. The adaptive control execution module adjusts the rolling pressure in real time based on these control parameters. This mutual cooperation enables the rolling pressure to adapt to changes in the actual breakage state of the tea leaves and environmental conditions. This breaks away from the limitations of traditional fixed pressure curves or fixed time programs, ensuring that the entire system has the ability to adaptively adjust and intelligently control.

[0025] 5. The system achieves closed-loop control through a combination of a cell damage rate identification module that identifies the current damage rate in real time, a multi-parameter coupling optimization module that calculates the damage rate deviation and generates correction control parameters, and an adaptive control execution module that adjusts the actual kneading pressure according to the control parameters. This allows the system to continuously monitor the deviation between the damage rate and the target value during the kneading process and correct it in a timely manner, thus achieving precise closed-loop control of the damage rate and ensuring that the entire system has the advantages of high stability and good product quality consistency.

[0026] 6. Through the cooperation of the temperature correction unit, moisture content correction unit, breakage rate deviation calculation unit, and coupling calculation unit of the multi-parameter coupling optimization module, the system can comprehensively consider the coupled influence of three key process parameters—breakage rate deviation, tea temperature, and tea moisture content—on the rolling pressure. It adopts a layered coupling strategy to generate optimized control parameters, ensuring that the entire system has the control capability of multi-parameter collaborative optimization and strong environmental adaptability. Attached Figure Description

[0027] The invention will be further understood from the following description taken in conjunction with the accompanying drawings. The components in the drawings are not necessarily drawn to scale, but rather the emphasis is on illustrating the principles of the embodiments. In different views, the same reference numerals designate the same parts.

[0028] Figure 1 This is a front view of the kneading machine of the present invention.

[0029] Figure 2 for Figure 1 Partial cross-sectional view at point AA.

[0030] Figure 3 for Figure 1Enlarged diagram of B in the diagram.

[0031] Figure 4 for Figure 2 Enlarged diagram of section C

[0032] Figure 5 for Figure 2 Enlarged schematic diagram of section D in the middle.

[0033] Figure 6 This is a schematic diagram of the overall framework of the dynamic control system for tea rolling according to the present invention.

[0034] Explanation of reference numerals in the attached drawings: 1. Kneading disc; 2. Frame; 3. Upright pole; 4. Fixed base; 5. Kneading motor; 6. First actuating rod; 7. First fixed rod; 8. Kneading drum; 9. Connecting rod; 10. Tea pressing plate; 11. Placement chamber; 12. Hydraulic drive rod; 13. Pressure adjusting rod; 14. Upright plate; 15. Negative pressure pipeline; 16. Limiting seat; 17. Support rod; 18. Liquid collection channel; 19. Conductivity sensor; 20. Filter screen; 21. Protrusion; 22. Second fixed rod; 23. Second actuating rod; 24. Hydraulic drive mechanism; 25. Temperature compensation sensor; 26. Vacuum pump; 27. Pressure sensor; 28. Central area; 29. ​​Middle area; 30. Edge area; 31. Kneading gap; 32. Electric heater. Detailed Implementation

[0035] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention. Furthermore, the accompanying drawings of the present invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated beforehand. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of protection of the present invention.

[0036] Example 1: According to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 ,as well as Figure 6 As shown, this embodiment provides a dynamic control system for tea rolling based on multi-parameter coupling optimization, including an exudate conductivity detection module, a cell disruption rate identification module, a multi-parameter coupling optimization module, and an adaptive control execution module. The exudate conductivity detection module detects the conductivity of the tea exudate in real time during the rolling process.

[0037] The cell breakage rate identification module identifies the current cell breakage rate of the tea leaves based on the conductivity value detected by the exudate conductivity detection module; the multi-parameter coupling optimization module generates optimized kneading control parameters based on the breakage rate identified by the cell breakage rate identification module, combined with the tea leaf temperature and moisture content; the adaptive control execution module receives the control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the actual working parameters of the kneading machine.

[0038] The multi-parameter coupling optimization module includes a breakage rate deviation calculation unit, a temperature correction unit, a moisture content correction unit, and a coupling calculation unit. The breakage rate deviation calculation unit calculates the deviation between the current cell breakage rate identified by the cell breakage rate identification module and the preset target breakage rate. The temperature correction unit generates a temperature correction parameter based on the current tea temperature. The moisture content correction unit generates a moisture content correction parameter based on the current tea moisture content. The coupling calculation unit generates rolling control parameters based on the deviation value calculated by the breakage rate deviation calculation unit, the temperature correction parameter generated by the temperature correction unit, and the moisture content correction parameter generated by the moisture content correction unit.

[0039] The dynamic control system for tea rolling also includes a power supply and a central processing unit (CPU). The CPU is electrically connected to the exudate conductivity detection module, the cell disruption rate identification module, the multi-parameter coupling optimization module, and the adaptive control execution module. Based on the CPU, the CPU centrally controls these modules and stores process and control data in a memory or register for querying and retrieval. In this embodiment, the CPU can be implemented using an industrial computer, a programmable logic controller (PLC), or an embedded microcontroller. Specifically, it can be a Siemens S7-1200 series PLC, a Schneider Modicon M221 series PLC, an STM32F407 series microcontroller, or an Advantech industrial computer.

[0040] like Figure 2 As shown, the lower end face of the kneading disc 1 is provided with a storage cavity, and the central processing unit is disposed in the storage cavity. In addition, the lower end face of the kneading disc 1 is connected to a frame 2, so that the kneading disc 1 is in a horizontal and vertical state.

[0041] In addition, the power supply device is used to convert the mains power to the voltage level required for the normal operation of each module of the system, providing a stable power supply for the sensors, central processing unit, exudate conductivity detection module, cell disruption rate identification module, multi-parameter coupling optimization module, and adaptive control execution module. In this embodiment, the power supply device includes an AC power supply section and a DC power supply section: the AC power supply supplies 220V mains power to high-power equipment such as motors and heating devices in the adaptive control execution module; the DC power supply converts 220V mains power to 24V DC power to supply low-power equipment such as sensors and central processing unit, and further converts it to 5V or 3.3V to power some sensors. The specific structure and circuit design of the power supply device are conventional technical means well known to those skilled in the art, and can be selected and configured according to the actual power requirements of the system, and will not be described in detail in this embodiment.

[0042] Optionally, the exudate conductivity detection module includes a layered detection structure, which divides the collection space at the bottom of the kneading disc 1 into multiple independent collection areas along the radial direction. Each area is provided with an independent exudate collection channel 18 and a conductivity detection unit.

[0043] The exudate collection channels 18 are distributed radially at equal intervals along the bottom of the kneading disc 1, wherein the conductivity detection unit is disposed in the exudate collection channels 18.

[0044] like Figure 4 As shown, the front end of the exudate collection channel 18 (the end near the kneading disc 1) is provided with a filter screen 20. The filter screen 20 is provided with at least two different pore sizes so that the contents released by the damaged cells can enter the exudate collection channel 18.

[0045] The conductivity detection unit includes a conductivity sensor 19, a temperature compensation sensor 25, and a data transmission interface. The conductivity probe is fixed to the bottom wall of the exudate collection channel 18 via a threaded connection and is coaxially arranged with the exudate collection channel 18. At the same time, the electrode of the conductivity probe is completely submerged in the exudate during measurement. The temperature sensor is integrated with the conductivity probe or installed adjacent to it in the same collection channel to ensure that the actual temperature of the exudate is measured.

[0046] Both the conductivity sensor 19 and the temperature compensation sensor 25 are connected to the data transmission interface via signal lines. The data transmission interface collects the measurement signals from the two sensors and sends them to the central processing unit via an industrial communication protocol.

[0047] The complete process of real-time detection of the electrical conductivity of tea exudate during the rolling process is as follows:

[0048] The pressing board applies downward pressure (0.3~0.8 MPa), and the kneading disc 1 begins to rotate (30~70 r / min). Under the action of pressure and shear force, the cell tissue of the tea leaves gradually breaks down; the broken cells release their contents, including tea polyphenols, amino acids, theophylline, and potassium ions (K). + ), calcium ions (Ca 2+ ), magnesium ions (Mg 2+ Electrolytes such as ) form tea exudate; under the action of gravity and kneading motion, the exudate seeps downward from the tea layer, flows through the gaps between the ridges on the surface of the kneading disc 1, and collects at the bottom of the kneading disc 1;

[0049] The bottom of the kneading disc 1 is designed with a concentric circle partition structure, including a central area 28 collection holes, an intermediate area 29 collection ring, and an edge area 30 collection ring. Micropores are opened at the bottom of each area, and the exudate enters the corresponding independent collection channel through the micropores.

[0050] Applying a slight negative pressure (-50 to -200 Pa) within the collection channel accelerates the directional flow of exudate from the tea leaf layer to the collection channel, reducing the response time from 5-8 minutes to 2-3 minutes.

[0051] In this embodiment, the conductivity is significantly affected by temperature; for every 1°C increase in temperature, the conductivity increases by approximately 2%. Since the temperature of the tea leaves changes during the rolling process (affected by factors such as ambient temperature and heat generated by rolling friction), without temperature compensation, the conductivity data measured at different times cannot be directly compared, affecting the accuracy of damage rate identification.

[0052] Temperature compensation is used to convert the conductivity measured at different temperatures into conductivity values ​​at the standard temperature (25℃), eliminating the interference of temperature fluctuations on the measurement results and ensuring that the conductivity data collected throughout the kneading process (0~25 minutes) are comparable, thereby accurately reflecting the true trend of cell damage.

[0053] In this embodiment, a Pt100 or Pt1000 platinum resistance temperature sensor is used.

[0054] In addition, a measurement process of conductivity sensor 19 is provided: under the action of kneading pressure, the cells of tea leaves are broken and release contents to form exudate. The exudate flows down from the tea leaf layer, passes through the micropores (pore diameter 0.3-0.8mm) at the bottom of the kneading disc 1, and enters the independent collection channels of the corresponding areas (central area 28 / middle area 29 / edge area 30).

[0055] A conductivity sensor 19 is installed within the collection channel, with its electrode portion immersed in the collected exudate to ensure full contact between the electrode and the exudate. The conductivity sensor 19 measures the conductivity of the immersed exudate. The exudate contains electrolyte ions (mainly K+) released from tea leaves. + Ca 2+ Mg 2+ The concentration of these ions directly reflects the degree of cell damage—the more severe the cell damage, the more ions are released, and the higher the conductivity of the exudate. The conductivity sensor 19 obtains the current conductivity value of the exudate through its built-in measurement mechanism. The conductivity sensor 19 converts the measured conductivity value into an electrical signal (usually an analog voltage signal or a digital signal), and outputs it to the data transmission interface via a signal line. The output data is: the current conductivity value σ of the exudate. t The unit is millisiemens per centimeter (mS / cm). The temperature-compensated sensor 25 measures the temperature of the exudate and outputs the temperature value T (unit: °C).

[0056] The conductivity value σ output by the conductivity sensor 19 t The temperature value T output by the temperature compensation sensor 25 and the temperature value T are simultaneously transmitted to the data transmission interface via their respective signal lines. The data transmission interface receives the conductivity value σ. t After obtaining the temperature value T, considering the effect of temperature on conductivity (conductivity increases with increasing temperature), the conductivity value is temperature compensated and converted to the conductivity value σ at the standard temperature (25℃). 25 This eliminates the effects of temperature fluctuations. The data transmission interface will process the conductivity value σ. 25 Information such as temperature value T, sensor number, and timestamp is packaged and sent to the central processing unit via RS485 communication bus.

[0057] Optionally, the layered detection structure divides the bottom of the kneading disc 1 radially from the center outward into three independent collection areas: a central area 28, a middle area 29, and an edge area 30.

[0058] like Figure 2 and Figure 5 As shown, the layered detection structure divides the bottom of the kneading disc 1 radially from the center outward into three independent collection areas: a central area 28, a middle area 29, and an edge area 30.

[0059] Central Zone 28: Located in the center of the kneading disc 1, it is equipped with independent collection holes and collection pipes;

[0060] Intermediate Zone 29: Located outside the central zone 28, it is circular in shape and has an independent collection ring trough and collection pipeline;

[0061] Edge zone 30: Located at the edge of the kneading disc 1, it is circular and has an independent collection ring groove and collection pipeline.

[0062] Micropores or interceptors are created at the bottom of each region, and the exudate from each region can only enter the corresponding independent collection channel through the micropores of that region, ensuring that the exudates from the three regions do not mix.

[0063] Each independent collection channel is equipped with a complete conductivity detection unit, including a conductivity sensor 19, a temperature compensation sensor 25, and a data transmission interface. Specifically, the central processing unit sends measurement commands to the three conductivity detection units simultaneously every 30 seconds, triggering a new round of conductivity and temperature measurements. The three detection units identify each other via device addresses on the RS485 bus and respond to the measurement commands accordingly. The three conductivity detection units perform measurement operations simultaneously, each independently completing the conductivity and temperature measurements: conductivity sensor 19 measures the conductivity of the exudate in its area and outputs σt; temperature compensation sensor 25 measures the temperature of the exudate in its area and outputs T; the data transmission interface performs temperature compensation processing to obtain the standardized conductivity σ25.

[0064] At the end of each measurement cycle, the central processing unit (CPU) sequentially queries the detection units of the three regions via the RS485 bus to collect the following data: conductivity σA and temperature TA of the central region 28; conductivity σB and temperature TB of the middle region 29; and conductivity σC and temperature TC of the edge region 30. The CPU stores this data in its local database, establishing a time-series record. The CPU ensures that the measurement timestamps of the three regions are consistent, with an error of less than 1 second, making the data from the three regions comparable at the same time. This facilitates synchronous calculation and weighted averaging by the subsequent cell damage rate identification module.

[0065] The central zone 28, located at the center of the rolling disc 1, experiences higher rolling pressure and a longer tea-tea retention time, resulting in relatively higher cell damage and thus typically higher exudate conductivity. The middle zone 29, with moderate pressure and movement, is the most representative area for rolling effect, exhibiting moderate exudate conductivity. The edge zone 30, located at the edge of the rolling disc 1, experiences relatively lower rolling pressure but greater movement, with frequent tea-tea agitation and relatively lower cell damage, resulting in typically lower exudate conductivity. By detecting the conductivity differences in each zone, the damage state of the tea-tea at different locations on the rolling disc 1 can be comprehensively reflected, avoiding the insufficient representativeness caused by single-point detection.

[0066] By combining the layered detection structure of the exudate conductivity detection module with the collection of conductivity data at different radial positions (center area 28, middle area 29, and edge area 30) of the kneading disc 1, and the weighted average calculation of the overall breakage rate by the cell damage rate identification module, the system can identify the differences in tea breakage at different positions within the kneading space and obtain spatial distribution information. This solves the problem in existing technologies that can only detect single points and cannot reflect the unevenness of breakage in the kneading space, ensuring that the entire system has the ability to comprehensively perceive the state of the kneading space and improve the accuracy of breakage rate identification.

[0067] Optionally, the cell damage rate identification module identifies the damage rate by establishing a quantitative mapping relationship between the exudate conductivity and the cell damage rate, and calculates the difference between the measured conductivity and the benchmark conductivity calibrated before kneading. Combined with a preset conductivity-damage rate conversion coefficient, the cell damage rate of the current tea leaves is obtained by inversion.

[0068] For the three independent collection areas—central area 28, intermediate area 29, and edge area 30—the cell damage rate identification module applies the same inversion algorithm to calculate the damage rate of each area.

[0069] Taking the central region 28 as an example, the calculation method is as follows: First, obtain the measured conductivity σA of the central region 28 (which has been temperature compensated and is the conductivity at a standard temperature of 25 degrees Celsius).

[0070] Secondly, the baseline conductivity σ0, calibrated before kneading, is used. The baseline conductivity σ0 is obtained by collecting initial conductivity data of the exudate from each area and calculating the average value within the first 3 minutes after kneading begins. Since the degree of cell damage in the tea leaves is very low during the initial kneading stage, the conductivity at this time mainly reflects the small amount of tea juice naturally exuded from the surface of the tea leaves, and can be used as a reference value for subsequent calculations. In this embodiment, the typical value range of the baseline conductivity σ0 is 0.2 to 0.5 millisiemens per centimeter (mS / cm).

[0071] The cell damage rate identification module calculates the difference between the measured conductivity and the reference conductivity: The difference reflects the increase in the release of electrolyte ions due to cell damage during the kneading process.

[0072] Finally, using the preset conductivity-damage rate conversion coefficient k, the cell damage rate DA in the central region is calculated through a linear inversion formula:

[0073] Wherein, k is the conductivity-damage rate conversion coefficient, expressed as a percentage per millisiemens per centimeter (% / (mS / cm)). This coefficient is determined through an offline calibration experiment. The specific method of the calibration experiment is as follows: samples of the same variety and tenderness as the tea leaves to be rolled are selected and rolled under standard rolling conditions. Samples are taken periodically during the rolling process, and the conductivity of the exudate and the actual cell damage rate determined by microscopic observation or staining are measured simultaneously. A correspondence between conductivity and damage rate is established, and the conversion coefficient k is determined through linear regression fitting. In this embodiment, the typical value range of k is 8 to 12 percentage points per millisiemens per centimeter. In this embodiment, the value of k is set to 10% / (mS / cm).

[0074] Using the same calculation method, calculate the breakage rate DB in the middle zone and the breakage rate DC in the edge zone respectively:

[0075] ;

[0076] It should be noted that the same baseline conductivity σ0 and conversion coefficient k are used in the three regions because the tea varieties, tenderness, and processing conditions are the same, and the quantitative relationship between conductivity and breakage rate is also consistent.

[0077] By combining the conductivity sensor of the exudate conductivity detection module to measure the conductivity of the exudate with the conductivity-damage rate inversion algorithm of the cell damage rate identification module, the system fully utilizes the electrochemical properties of the exudate as a characterization parameter of the degree of damage. This transforms the previously neglected or directly discharged exudate into a key detection target, solving the problems of ineffective utilization of exudate characteristics and single detection methods in existing technologies. This ensures that the entire system has the advantages of multi-dimensional information acquisition and high-sensitivity detection.

[0078] In addition, the cell damage rate identification module identifies the cell damage rate of each layer of tea leaves and calculates the overall damage rate by weighted average. The weighting coefficient is set according to the difference in the pressure of each layer of tea leaves.

[0079] Specifically, after obtaining the damage rates DA, DB, and DC for each region, the cell damage rate identification module calculates the overall damage rate Dtotal using a weighted average method.

[0080] ;

[0081] Wherein, wA, wB, and wC are the weighting coefficients for the central area, intermediate area, and edge area, respectively. In this embodiment, when calculating the overall damage rate, the weighting coefficient for the central area is 0.3, the weighting coefficient for the intermediate area is 0.5, and the weighting coefficient for the edge area is 0.2, thereby reflecting the actual working conditions of the central area experiencing high pressure and long residence time, the intermediate area experiencing moderate force, and the edge area experiencing relatively low pressure but intense movement.

[0082] The damage rate deviation calculation unit is responsible for calculating the deviation between the current cell damage rate and the target damage rate, providing feedback signals for subsequent control and adjustment.

[0083] In this embodiment, a target breakage rate Dtarget is set, which is preset according to the requirements of the kneading process. Furthermore, in the implementation method using segmented target scheduling, the target breakage rate is dynamically adjusted with each kneading stage.

[0084] This embodiment divides the kneading process into three stages: light kneading, main kneading, and shaping.

[0085] 1) Light rolling period (0 to 8 minutes after the start of rolling): The target breakage rate is set at 15% to 25%, and in this example, Dtarget=20%. The purpose of this stage is to slightly damage the tea leaves and promote the initial seepage of tea juice, in preparation for subsequent rolling.

[0086] 2) Main kneading stage (8 to 20 minutes after kneading begins): The target breakage rate is set at 45% to 65%, and in this embodiment, Dtarget=55%. This stage is the core stage of kneading, which requires sufficient cell breakage to fully release the tea polyphenols, amino acids and other internal components, forming the color and aroma of the tea.

[0087] 3) Shaping period (20 to 25 minutes after the start of rolling): The target breakage rate is maintained at the level of the main rolling period, i.e., Dtarget=55%. The main purpose of this stage is to shape the tea leaves, making them curled and tight, while maintaining the achieved breakage level and avoiding excessive breakage that would lead to excessive loss of tea juice.

[0088] For a simplified implementation that does not employ segmented target scheduling, a fixed target breakage rate can be set, for example, Dtarget=50%, which remains constant throughout the kneading process.

[0089] Specifically, the cell damage rate deviation calculation unit obtains the current overall cell damage rate Dtotal from the cell damage rate identification module. This data is updated every 30 seconds, synchronized with the conductivity detection cycle.

[0090] The breakage rate deviation ΔD is defined as the difference between the target breakage rate and the current breakage rate: ;

[0091] Among them, when When the current breakage rate is lower than the target value, the cell damage is insufficient, and the kneading pressure needs to be increased to accelerate the breakage speed; when When the current breakage rate reaches the target value and the degree of breakage is appropriate, the current kneading pressure should be maintained; when When the current breakage rate exceeds the target value, it indicates that the cells are excessively damaged. It is necessary to reduce the kneading pressure to slow down the breakage rate and avoid excessive loss of tea juice and increase tea leaf fragments.

[0092] The temperature correction unit generates temperature correction parameters based on the real-time temperature of the tea leaves and uses them to correct the baseline kneading pressure. Temperature has a significant impact on the toughness and breakage difficulty of the tea leaf cell walls: when the temperature is low, the cell walls are tougher and less prone to breakage, requiring an appropriate increase in kneading pressure; when the temperature is high, the cell walls soften and are more prone to breakage, requiring an appropriate decrease in kneading pressure to avoid excessive breakage.

[0093] The temperature of the tea leaves is measured using a contact temperature sensor. In this embodiment, a platinum resistance temperature sensor (PT100 or PT1000) is used. The sensor probe is embedded in the upper surface (end face) of the kneading disc 1. The probe is flush with or slightly protrudes 1 to 2 millimeters from the disc surface, ensuring direct contact with the tea leaves during kneading to measure their true temperature in real time. The sensor transmits the temperature data to the control processor via an RS485 communication interface or an analog signal output (4~20mA).

[0094] In this embodiment, since three temperature sensors (not shown in the figure) are set in three areas, three temperature measurements can be obtained: TA (center area temperature), TB (middle area temperature), and TC (edge ​​area temperature). There are two processing methods when generating temperature correction parameters: Method 1: Using a weighted average temperature. The overall average temperature is calculated based on the representativeness of each area. The weighting coefficients are consistent with those used in the breakage rate identification, i.e., wA = 0.3, wB = 0.5, and wC = 0.2. This average temperature reflects the average temperature state of the tea leaves across the entire range of the kneading disc.

[0095] In this embodiment, the temperature correction parameter αT is generated according to a segmented rule based on the current tea temperature T. This embodiment divides the temperature range into five intervals, each corresponding to a different correction coefficient:

[0096] First temperature range (25°C ≤ T ≤ 30°C): This temperature range is the optimal temperature range for tea rolling, with moderate cell wall toughness and suitable difficulty in breaking the cells. The temperature correction parameter is set to the baseline value, i.e., αT = 1.0. At this temperature, the baseline rolling pressure does not need to be corrected.

[0097] Low temperature range (T < 25 degrees Celsius): When the temperature is below the optimal range, the cell wall becomes more resilient and difficult to break, requiring increased kneading pressure. This embodiment is further subdivided into two ranges:

[0098] When 20 degrees Celsius ≤ T < 25 degrees Celsius, the temperature correction parameter is calculated using linear interpolation: ;

[0099] When T < 20 degrees Celsius, the temperature correction parameter is taken as the lower limit: αT = 0.85;

[0100] High temperature range (T>30 degrees Celsius): When the temperature is higher than the optimal range, the cell walls soften and are easily damaged, so the kneading pressure needs to be reduced.

[0101] This embodiment is further subdivided into two intervals: when 30 degrees Celsius < T ≤ 35 degrees Celsius, the temperature correction parameter is calculated using linear interpolation. ;

[0102] When T > 35 degrees Celsius, the temperature correction parameter takes the upper limit: αT = 1.15;

[0103] In this embodiment, the temperature correction parameter is set based on the following physical mechanism: the cell wall of tea leaves is mainly composed of cellulose, hemicellulose, and pectin, and the mechanical strength of these substances is significantly affected by temperature. Specifically, when the temperature decreases, the molecular chain motion weakens, the material rigidity increases, and a greater external force is required to rupture the cell wall; when the temperature rises, the molecular chain motion intensifies, the material flexibility increases, and the cell wall is more prone to deformation and damage.

[0104] The moisture content correction unit generates moisture content correction parameters based on the real-time moisture content of the tea leaves and corrects the baseline rolling pressure. Moisture content has a significant impact on the turgor pressure and the difficulty of cell breakage in tea leaves: when the moisture content is low, the cell turgor pressure is insufficient, the cell walls are dry and hard, and breakage is difficult, requiring an increase in rolling pressure; when the moisture content is high, the cell turgor pressure is too high, and the cells are prone to rupture, requiring a decrease in rolling pressure to avoid excessive loss of tea juice.

[0105] The moisture content of tea leaves is measured using a near-infrared moisture analyzer. Based on the principle of near-infrared spectral absorption, water molecules strongly absorb near-infrared light at specific wavelengths (such as around 1450 nm and 1940 nm). By measuring the absorption intensity of near-infrared light by the tea sample and combining this with a calibration curve, the moisture content of the tea leaves can be calculated. In this embodiment, the near-infrared moisture analyzer is installed on the side wall of the kneading drum, with the measuring light path penetrating the tea leaf layer or using diffuse reflection mode to measure the moisture content of the tea leaves in real time. Simultaneously, the near-infrared moisture analyzer transmits the moisture content data to the control processor via an RS485 communication interface.

[0106] Optionally, the moisture content correction parameter is determined in segments according to the moisture content range of the tea leaves: when the moisture content of the tea leaves is within the first moisture content range, it is determined as the first correction coefficient; when the moisture content of the tea leaves is below the first moisture content range, it is determined as the second correction coefficient, which is less than the first correction coefficient, in order to reduce the rolling pressure and prevent excessive damage to the tea leaves; when the moisture content of the tea leaves is above the first moisture content range, it is determined as the third correction coefficient, which is greater than the first correction coefficient, in order to increase the rolling pressure and overcome the problem of cells not being easily damaged due to high moisture content.

[0107] At low moisture content, the cellulose, hemicellulose, and pectin in the cell walls lose water and shrink, making the material brittle. Under rolling pressure, the cell walls are prone to brittle fracture, resulting in excessive breakage as the tea leaves crumble into fine fragments. Excessive breakage increases the breakage rate and reduces the yield of whole tea leaves, affecting the appearance and quality of the tea. Simultaneously, excessive cell breakage leads to excessive loss of tea juice, affecting the retention of the tea's internal components. Therefore, under low moisture content conditions, it is necessary to reduce rolling pressure and use a gentle rolling method to prevent excessive breakage of the tea leaves. At high moisture content, the cell walls fully absorb water and swell, making the material resilient.

[0108] Under the same rolling pressure, cell walls are less prone to breakage, resulting in a problem of cell susceptibility. Insufficient rolling leads to insufficient tea juice extraction and inadequate release of tea polyphenols and amino acids, affecting the aroma and flavor of the tea. Simultaneously, a low cell breakage rate results in loosely curled tea leaves with a loose appearance. Therefore, under high moisture content conditions, it is necessary to increase the rolling pressure and intensity to overcome the cell wall toughness issue that hinders cell breakage.

[0109] The moisture content correction parameter αW is generated according to a segmented rule based on the current moisture content W of the tea leaves. This embodiment divides the moisture content range into five intervals, each corresponding to a different correction coefficient:

[0110] First moisture content range (60%≤W≤65%): This range represents the optimal moisture content for tea leaf rolling, where cell wall mechanical properties are moderate and the breakage pattern is reasonable. The moisture content correction parameter is set to the baseline value, i.e., αW = 1.0. At this moisture content, the baseline rolling pressure does not require correction.

[0111] Low moisture content range (W < 60%): When the moisture content is below the optimal range, the cell walls become brittle and easily break down, requiring a reduction in kneading pressure.

[0112] This embodiment is further subdivided into two intervals:

[0113] When 58% ≤ W < 60%, linear interpolation is used to calculate the moisture content correction parameter: ;

[0114] When W < 58%, the moisture content correction parameter is taken as the lower limit: αW = 0.75

[0115] High moisture content range (W > 65%): When the moisture content is higher than the optimal range, the cell walls become tough and less prone to breakage, requiring increased kneading pressure. This embodiment is further subdivided into two ranges:

[0116] When 65% < W ≤ 68%, linear interpolation is used to calculate the moisture content correction parameter: ;

[0117] When W > 68%, the moisture content correction parameter takes the upper limit: αW = 1.24;

[0118] In this embodiment, the moisture content of the tea leaves gradually decreases during the rolling process, from an initial 60-70% to 55-65% at the end. The moisture content correction unit can track the changes in moisture content in real time and dynamically adjust the correction parameters to ensure that the rolling process is always under reasonable pressure control.

[0119] Optionally, the coupling calculation unit generates the kneading control parameters in the following manner: the preset reference kneading pressure is coupled with the temperature correction parameter in a first coupling operation, and then coupled with the moisture content correction parameter in a second coupling operation to obtain the corrected reference pressure. Then, the corrected reference pressure is adjusted by the deviation value calculated by the breakage rate deviation calculation unit to generate a real-time kneading pressure control value as the kneading control parameter.

[0120] Optionally, the temperature correction parameter is determined in segments according to the tea temperature range: when the tea temperature is within the first temperature range, it is determined as the first correction coefficient; when the tea temperature is below the first temperature range, it is determined as the second correction coefficient, which is less than the first correction coefficient, to reduce the kneading pressure; and when the tea temperature is above the first temperature range, it is determined as the third correction coefficient, which is greater than the first correction coefficient, to increase the kneading pressure.

[0121] The coupling calculation unit is the core unit of the multi-parameter coupling optimization module. It is responsible for receiving the deviation value ΔD output by the breakage rate deviation calculation unit, the temperature correction parameter αT output by the temperature correction unit, and the moisture content correction parameter αW output by the moisture content correction unit. Combined with the preset benchmark kneading pressure P0, the final kneading control parameters are generated through the multi-parameter coupling algorithm.

[0122] The reference kneading pressure P0 is a pre-set process parameter stored in the process parameter library of the control processor. At the beginning of each calculation cycle, the coupled calculation unit reads the reference pressure value corresponding to the current stage from the process parameter library. The reference kneading pressure P0 is determined by pre-setting it according to the tea variety, tenderness, and kneading stage. For tender green teas (such as Longjing and Biluochun), the reference pressure is usually set to 0.3 to 0.5 MPa; for medium-tender green teas (such as Maofeng and Cuiluo), the reference pressure is set to 0.4 to 0.6 MPa; and for coarser green teas (such as pan-fired and oven-dried green teas), the reference pressure is set to 0.5 to 0.8 MPa.

[0123] This embodiment uses medium-tender green tea as an example, setting the reference pressure P0 = 0.5 MPa. For the implementation using segmented target scheduling, the reference pressure can also be adjusted according to the rolling stage: a lower reference pressure (e.g., 0.3 MPa) is used during the light rolling stage, a standard reference pressure (e.g., 0.5 MPa) is used during the main rolling stage, and the reference pressure is maintained or slightly reduced (e.g., 0.45 MPa) during the shaping stage. When the system switches from one stage to the next, the control processor automatically updates the reference pressure value in the process parameter library, and the coupled calculation unit can read the updated value in the next calculation cycle.

[0124] The coupling calculation unit performs a first coupling operation (multiplication) with the preset benchmark kneading pressure P0 and the temperature correction parameter αT, and then performs a second coupling operation (multiplication) with the moisture content correction parameter αW to obtain the corrected benchmark pressure Pbase: ;

[0125] when At low temperatures, the baseline pressure is reduced because the cell wall becomes more resilient at low temperatures, so the same damage effect can be achieved with less pressure.

[0126] when At high temperatures, the baseline pressure is increased because the cell walls soften at high temperatures, requiring greater pressure to prevent them from breaking down too quickly.

[0127] when At low water content, the reference pressure is reduced because the cell turgor pressure is insufficient and the cell wall is dry and hard at low water content, thus using a smaller pressure to avoid excessive cell breakage; when At high water content, the baseline pressure is increased because the cells turgor pressure is high and they are prone to rupture at high water content, requiring greater pressure to precisely control the rate of rupture.

[0128] The deviation value ΔD output by the breakage rate deviation calculation unit is converted into the pressure adjustment amount ΔP through proportional adjustment. The conversion formula is as follows: Wherein, Kp is the proportionality coefficient, expressed in megapascals per percentage (MPa / %), used to convert the dimensionless breakage rate deviation into a pressure-dimensional adjustment. The proportionality coefficient Kp reflects the response sensitivity of the control system; the larger the Kp value, the more aggressive the system response to the deviation; the smaller the Kp value, the smoother the system response. In this embodiment, Kp is set to 0.01 MPa / %, meaning that for every 1% increase in the breakage rate deviation, the pressure adjustment increases by 0.01 MPa.

[0129] For example, when ΔD=10% (the current breakage rate is 10% lower than the target), then ΔP=0.01×10=0.1 MPa, which means that the pressure needs to be increased by 0.1 MPa; when ΔD=-5% (the current breakage rate is 5% higher than the target), then ΔP= 0.01×(-5)=-0.05 MPa, which means that the pressure needs to be decreased by 0.05 MPa.

[0130] To avoid over-response or oscillation, this embodiment sets a limit on the pressure regulation ΔP, restricting its absolute value to no more than 0.2 MPa, i.e., -0.2 MPa ≤ ΔP ≤ 0.2 MPa. If the calculated ΔP exceeds this range, the boundary value is taken.

[0131] The corrected baseline pressure Pbase is added to the pressure adjustment amount ΔP to generate the real-time kneading pressure control value P as the kneading control parameter: ;

[0132] Among them, the environmental condition correction function: αT and αW reflect the influence of temperature and moisture content on the difficulty of damage, and adjust the pressure benchmark; in addition, the feedback adjustment function of the damage rate deviation: ΔP reflects the gap between the current damage rate and the target damage rate, and dynamically corrects the pressure.

[0133] The synergistic effect of the two-layer coupling mechanism enables optimized control of multiple parameters.

[0134] In other embodiments, if the coupled calculation unit only generates the kneading pressure control value P as the kneading control parameter, single-parameter adaptive control based on the breakage rate is achieved. This is the most basic implementation and is suitable for kneading machines equipped only with a pressure regulating actuator.

[0135] For kneading machines equipped with a more sophisticated control system, the coupling calculation unit is further extended to a multi-parameter collaborative control mode. While generating the kneading pressure control value P, it also generates the kneading speed control value V and the kneading temperature control value T, thereby achieving coordinated optimization and adjustment of pressure, speed, and temperature.

[0136] In this embodiment, the coupled calculation unit generates a kneading speed control value V based on the breakage rate deviation. When the breakage rate deviation ΔD > 0 (insufficient breakage), the coupled calculation unit generates not only a larger kneading pressure control value but also a higher kneading speed control value, thereby accelerating the breakage rate by enhancing the dynamic intensity of kneading; when the breakage rate deviation ΔD < 0 (excessive breakage), the coupled calculation unit generates a lower kneading speed control value, thereby slowing down the breakage rate.

[0137] The formula for calculating the speed control value V by the coupled calculation unit is: ;

[0138] Where: V is the output kneading speed control value, in revolutions per minute (r / min); V0 is the reference kneading speed, which is 50 revolutions per minute in this embodiment; Kv is the speed adjustment coefficient, which is 0.5 revolutions per minute per percentage ((r / min) / %) in this embodiment; ΔD is the deviation value output by the breakage rate deviation calculation unit, in percentage (%).

[0139] The above formula converts the breakage rate deviation into a speed adjustment amount, achieving dynamic speed control. To avoid excessive speed fluctuations affecting tea quality or damaging equipment, the coupled calculation unit sets a limit range for the speed control value V: 30 r / min ≤ V ≤ 70 r / min. If the calculated V exceeds this range, the boundary value is taken.

[0140] In another embodiment, the coupling calculation unit also generates a kneading temperature control value T_target to maintain the tea temperature within the optimal range. The coupling calculation unit obtains the current tea temperature T from the temperature correction unit, and when it detects that the tea temperature deviates from the optimal range (25 to 30 degrees Celsius), it generates a target temperature control value to drive the temperature adjustment unit to perform temperature regulation.

[0141] The coupling calculation unit generates the temperature control value T_target according to the following rules: When T < 25℃, the coupling calculation unit sets T_target = 27℃, and the temperature regulation unit starts the heating device after receiving this target value to raise the tea temperature; when 25℃ ≤ T ≤ 30℃, the tea temperature is within the optimal range, the coupling calculation unit sets T_target = T (maintaining the current temperature), and the temperature regulation unit does not start the temperature control device; when T > 30℃, the coupling calculation unit sets T_target = 28℃, and the temperature regulation unit starts the cooling device after receiving this target value to lower the tea temperature. The temperature regulation unit controls the activation time and intensity of the heating or cooling device based on the difference between the received target temperature T_target and the actual temperature T, gradually bringing the tea temperature closer to the target value.

[0142] At the end of each calculation cycle (30 seconds), the coupled calculation unit simultaneously outputs three control parameters: kneading pressure control value P (unit: MPa), kneading speed control value V (unit: r / min), and kneading temperature control value T_target (unit: ℃). These three control values ​​are transmitted to the pressure regulation unit, speed regulation unit, and temperature regulation unit of the adaptive control execution module through RS485 communication bus or independent analog signal line, respectively, to achieve multi-parameter coordinated control.

[0143] By simultaneously generating three control parameters—pressure, speed, and temperature—through a coupled computing unit, the system can influence the kneading process from multiple dimensions, improving the flexibility and precision of control. For example, when the breakage rate deviates significantly, the pressure and speed can be increased simultaneously to quickly correct the deviation; when the temperature deviates from the optimal range, temperature control can maintain the appropriate toughness of the cell walls, and pressure regulation can be used to achieve stable control.

[0144] Multi-parameter coordinated control requires additional speed regulation actuators (frequency converters) and temperature regulation actuators (heating devices), increasing system complexity and cost. For scenarios with low process requirements or limited equipment investment, single-parameter control based on kneading pressure can meet the needs.

[0145] Through the design of the above multi-parameter coupling optimization module, the coupling calculation unit can realize simple and efficient single-parameter control (generating only P), or it can be extended to fully functional multi-parameter collaborative control (generating P, V, and T_target simultaneously), meeting the needs of different application scenarios.

[0146] In addition, the system combines real-time acquisition of exudate conductivity data by the exudate conductivity detection module with the establishment of a quantitative mapping relationship between conductivity and damage rate by the cell damage rate identification module. This enables the system to convert changes in electrolyte ion concentration in the exudate into cell damage rate values ​​in real time, achieving online direct detection of cell damage rate, an essential indicator of the kneading process. This solves the problem in existing technologies where cell damage rate cannot be directly measured and can only be judged based on experience or detected afterward, ensuring that the entire system has the ability to control based on essential process parameters.

[0147] Optionally, the adaptive control execution module includes a pressure adjustment unit, a speed adjustment unit, and a temperature adjustment unit. The pressure adjustment unit receives the kneading pressure control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the pressurizing device of the kneading machine to change the kneading pressure applied to the tea leaves. The speed adjustment unit receives the kneading speed control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the rotation speed of the kneading drum to change the dynamic intensity of kneading. The temperature adjustment unit receives the kneading temperature control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the temperature of the kneading environment to maintain or change the temperature of the tea leaves.

[0148] The actual working parameters of kneading include at least one of kneading pressure, kneading speed, and kneading temperature.

[0149] The most basic and practical implementation of this invention is based on a single-parameter control method using kneading pressure. In this configuration, the adaptive control execution module includes only a pressure adjustment unit, which receives the kneading pressure control value P generated by the coupled calculation unit and adaptively adjusts the pressure application device of the kneading machine to change the kneading pressure applied to the tea leaves. Kneading speed and kneading temperature are not controlled variables in this embodiment, but are pre-set process parameters: the kneading speed is preset to a fixed value (e.g., 50 rpm) by the operator based on the tea variety and tenderness, and remains constant throughout the kneading process; the kneading ambient temperature depends on the natural balance between the workshop ambient temperature and the heat generated by kneading friction, and is not actively controlled. This single-parameter control method is simple in structure, low in cost, and highly reliable, and is suitable for most tea kneading scenarios. Practice shows that precise control of kneading pressure can effectively regulate the cell damage rate, meeting the process requirements for tea quality.

[0150] In addition, the kneading disc is located below the kneading tube, and the two are close to each other, with the gap between them just enough to form a kneading gap for the tea leaves; the kneading tube has a cavity for loading the tea leaves to be kneaded, and the kneading drum is equipped with a tea pressing plate.

[0151] like Figure 2As shown, the pressurizing device includes a support rod 17, a hydraulic drive mechanism 24, a hydraulic drive rod 12, a vertical plate 14, a limiting seat 16, a pressure adjusting rod 13, and a connecting rod 9. One end of the support rod 17 is connected to the outer wall of the kneading disc 1, and the other end of the support rod 17 is connected to the hydraulic drive mechanism 24. The limiting seat 16 is disposed on the outer wall of the kneading disc. One end of the vertical plate 14 is vertically fixedly connected to the upper end face of the limiting seat 16, and the other end of the vertical plate 14 faces away from the limiting seat. One side of the upper end face of the seat 16 extends out; the middle part of the pressure adjusting rod 13 is hinged to the end of the upright plate 14 away from the upper end face of the limiting seat 16 to form a fulcrum; one end of the connecting rod 9 is hinged to one end of the pressure adjusting rod 13 to form a first driving part; the other end of the pressure adjusting rod 13 is hinged to the driving end of the hydraulic driving rod 12 to form a second driving part; the other end of the connecting rod 9 extends into the kneading barrel 8 and is hinged to the end face of the tea pressing plate 10 away from the tea leaves to form a pressing part.

[0152] like Figure 2 As shown, when the hydraulic drive mechanism 24 drives the hydraulic drive rod 12 to extend, the pressure regulating rod 13 rotates along the fulcrum, thereby pressing the tea leaves through the connecting rod 9 and the tea pressing plate 10, thereby applying kneading pressure P to the tea leaves, thus prompting the tea leaves to be kneaded in the kneading disc 1.

[0153] This embodiment uses a hydraulic drive to adjust the kneading pressure. The hydraulic pressurization device includes a hydraulic pump, a hydraulic cylinder, a hydraulic drive rod 12, a pressure sensor 27, and a proportional relief valve. The hydraulic pump provides a high-pressure oil source to the system. The piston in the hydraulic cylinder moves up and down under the push of the hydraulic oil, driving the hydraulic drive rod 12 connected to the piston to extend and retract. The top of the hydraulic drive rod 12 is connected to a tea pressing plate. By controlling the extension of the hydraulic drive rod 12, the degree of compression of the tea leaves by the tea pressing plate is changed, thereby adjusting the kneading pressure.

[0154] When the hydraulic drive rod 12 extends, the tea pressing plate moves downward, increasing the pressure on the tea leaves; when the hydraulic drive rod 12 shortens, the tea pressing plate moves upward, decreasing the pressure on the tea leaves. The relationship between the extension L (in millimeters) of the hydraulic drive rod 12 and the kneading pressure P (in megapascals) was determined through experimental calibration.

[0155] Under standard conditions (20 kg tea leaves, 62% moisture content), the hydraulic drive rod was gradually extended while the actual kneading pressure was measured using a pressure sensor, and multiple sets of corresponding data were recorded. Linear regression fitting was performed on the calibration data to obtain the extension-pressure conversion relationship: ; or in reverse: ;

[0156] The coefficient 0.25 mm / MPa reflects the compression characteristics of the tea layer, and the constant term 5 mm represents the initial gap between the tea pressing board and the tea layer before they come into contact.

[0157] For every 0.1 MPa increase in kneading pressure, the hydraulic drive rod needs to extend by approximately 2.5 mm. For example, when the target pressure increases from 0.3 MPa to 0.5 MPa, the extension needs to increase from 12.5 mm to 17.5 mm, an increase of 5 mm.

[0158] It should be noted that the conversion relationship between rolling pressure and elongation is affected by factors such as tea leaf load, moisture content, and tenderness. For different operating conditions, the corresponding conversion coefficient can be obtained through recalibration. This calibration relationship is stored in the control processor as the basis for the conversion between elongation and pressure.

[0159] The system utilizes a cell damage rate identification module to identify the actual damage rate of tea leaves with different tenderness and moisture content in real time. A multi-parameter coupling optimization module automatically adjusts control parameters based on the damage rate deviation. An adaptive control execution module dynamically changes the kneading pressure. Through these interactions, the system can automatically adapt to the differences in physical properties of different batches of tea raw materials without the need for manual parameter resetting. This solves the problem in existing technologies where fixed process parameters cannot adapt to changes in raw materials and require frequent manual adjustments. The system ensures that it has the advantages of strong raw material adaptability and high ease of operation.

[0160] The pressure regulating unit is responsible for receiving the kneading pressure control value P output by the multi-parameter coupling optimization module, and adjusting the kneading pressure applied to the tea leaves by the tea pressing plate 10 by controlling the extension and retraction of the hydraulic drive rod.

[0161] The pressure regulating unit achieves precise pressure control through the following steps:

[0162] Step 1: Calculate the target elongation based on the pressure control value P and the calibration relationship: ;

[0163] Step 2: The displacement sensor (magnetostrictive or draw-wire type, accuracy 0.1 mm) on the hydraulic cylinder measures the current elongation L_current in real time;

[0164] Step 3: Calculate the deviation: ;

[0165] Step 4: Generate hydraulic control commands based on the deviation ΔL. The control processor employs a proportional control strategy, where the control command u is directly proportional to the deviation ΔL. Where Kp is the proportional coefficient, and in this embodiment, Kp = 50. The control command u outputs an analog voltage signal of 0 to 10 volts, which is sent to the proportional relief valve. The proportional relief valve adjusts the valve core opening according to the control signal, changes the hydraulic cylinder oil pressure, and drives the piston to move.

[0166] When ΔL > 0, the controller outputs a pressure boosting command to the proportional relief valve, increasing the hydraulic cylinder pressure and driving the piston downwards to increase the elongation. When ΔL < 0, it outputs a pressure reduction command, decreasing the hydraulic cylinder pressure and driving the piston upwards to decrease the elongation. The adjustment intensity of the control command is related to the magnitude of the deviation ΔL; a larger deviation results in faster adjustment, while a smaller deviation results in slower adjustment, achieving smooth pressure following.

[0167] Step 5: Repeat steps 2-4 every 100 milliseconds to form a displacement closed-loop control;

[0168] In addition, a pressure sensor (range 0-1 MPa, accuracy ±0.01 MPa) directly measures the actual kneading pressure. The control processor simultaneously monitors displacement and pressure feedback, forming a dual closed loop: a displacement loop ensures rapid response, and a pressure loop ensures precise control. When the deviation between the actual pressure and the target pressure exceeds ±0.05 MPa, the system fine-tunes the target elongation to compensate for the influence of changes in tea leaf characteristics.

[0169] The system employs a multi-parameter coupling optimization module that dynamically generates kneading control parameters based on real-time breakage rate deviation, temperature correction parameters, and moisture content correction parameters. An adaptive control execution module then adjusts the kneading pressure in real-time based on these control parameters. This mutual coordination allows the kneading pressure to adapt to changes in the actual breakage state of the tea leaves and environmental conditions. This overcomes the limitations of traditional fixed pressure curves or fixed time programs, solving the problem of fixed and singular kneading parameters in existing technologies that cannot adapt to differences in raw materials and process variations. This ensures the entire system has adaptive adjustment and intelligent control capabilities.

[0170] The speed adjustment unit receives the kneading speed control value V generated by the multi-parameter coupling optimization module and adaptively adjusts the rotation speed of the kneading drum 8 to change the dynamic intensity of kneading. That is, the central processing unit controls the rotation speed of the kneading motor 5 through a frequency converter and controls the rotation speed of the kneading motor 5 according to the kneading speed control value V. The kneading motor 5 is a three-phase asynchronous motor.

[0171] like Figure 1 As shown, the outer wall of the kneading disc 1 is provided with a first fixing seat 4 and a second fixing seat 4, which are respectively disposed on the periphery of the kneading disc 1.

[0172] There are a total of 3 first fixing seats 4 and second fixing seats 4, and the horizontal spacing between the first fixing seats 4 and the second fixing seats 4 is 60°. A vertical rod 3 is provided on the first fixing platform. One end of the vertical rod 3 is connected to the upper surface of the first fixing platform, and the other end of the vertical rod 3 extends out toward the side away from the fixing platform.

[0173] The outer wall of the kneading disc 1 is also provided with a first actuating rod 6, a second actuating rod 23, a first fixing rod 7 and a second fixing rod 22. One end of the first fixing rod 7 is connected to the outer wall of the kneading drum 8, and the other end of the first fixing rod 7 is hinged to one end of the first actuating rod 6 to form a first hinge part. The other end of the first actuating rod 6 extends upward toward the first fixed seat 4 and is hinged to the upright rod 3 to form a second hinge part.

[0174] One end of the second fixing rod 22 is connected to the outer wall of the kneading barrel 8, and the other end of the second fixing rod 22 is hinged to one end of the second actuating rod 23 to form a third hinge part. The other end of the second actuating rod 23 extends upward toward the second fixing seat 4 and is hinged to the upright rod 3 to form a second hinge part.

[0175] Since the first fixed seat 4, the second fixed seat 4, the upright rod 3, the kneading motor 5, the first actuating rod 6, the second actuating rod 23, the first fixed rod 7, and the second fixed rod 22 are arranged on the outer wall of the kneading drum 8, a kneading path with a controllable range of movement is formed around the outer perimeter of the kneading drum 8.

[0176] When the kneading motor 5 rotates, it drives the second actuating rod 23, the second fixing rod 22, the first actuating rod 6, the first fixing rod 7 and the kneading passage to rotate, and causes the tea leaves to be kneaded to be kneaded in the kneading gap 31, so that the tea leaves are kneaded in the kneading protrusion 21, and finally form kneaded tea leaves.

[0177] The frequency converter receives control signals (typically 0 to 10 volt analog signals or RS485 digital signals) from the central processing unit and speed regulation unit, converts them into motor drive frequencies (25 to 50 Hz), and thus regulates the motor speed. When the received speed control value V increases, the frequency converter increases the output frequency, the motor speed increases, and the speed of the kneading drum 8 increases accordingly; conversely, when V decreases, the speed of the kneading drum 8 decreases.

[0178] Variations in the rolling speed directly affect the dynamic intensity of the rolling: the higher the speed, the more vigorous the relative movement of the tea leaves on the rolling disc, the greater the shear force they experience, and the faster the breakage rate; the lower the speed, the slower the breakage rate. By coordinating the adjustment of speed and pressure, the breakage process can be controlled more flexibly.

[0179] The system utilizes a temperature correction unit to generate temperature correction parameters based on tea temperature to compensate for changes in cell wall toughness, a moisture content correction unit to generate moisture content correction parameters based on tea moisture content to compensate for changes in cell turgor pressure and brittleness, and a coupling calculation unit to couple the correction parameters to the reference pressure through multiplication. This mutual coordination enables the system to automatically adjust the pressure reference under different temperature and moisture content conditions, eliminating the influence of environmental factors on the difficulty of breakage. It solves the problem in existing technologies where inconsistent breakage effects under the same pressure are not considered due to changes in temperature and moisture content, ensuring that the entire system has the advantages of strong environmental adaptability and high control robustness.

[0180] The temperature control unit includes an electric heater 32, which is installed on the inner wall of the kneading drum 8 to heat the tea leaves by heating the drum wall.

[0181] The central processing unit controls the temperature of the tea leaves placed in the kneading barrel 8 by heating or cooling the tea leaves based on the difference between the target temperature T_target and the actual temperature T (measured by a temperature sensor), thereby regulating the temperature of the tea leaves.

[0182] When T < T_target, the temperature control unit activates the heating device, and the heating power is proportional to the temperature difference (T_target - T), thereby increasing the temperature of the tea leaves.

[0183] When T ≥ T_target, the temperature regulation unit shuts off the heating device, stopping the heat input to the tea leaves, and the tea temperature gradually decreases to a reasonable range through natural heat dissipation. The system achieves closed-loop control through a combination of mechanisms: a cell damage rate identification module to identify the current damage rate in real time; a multi-parameter coupling optimization module to calculate the damage rate deviation and generate correction control parameters; and an adaptive control execution module to adjust the actual kneading pressure according to the control parameters. This allows the system to continuously monitor and correct the deviation between the damage rate and the target value during the kneading process, achieving precise closed-loop control of the damage rate. This solves the problem of large quality fluctuations and poor consistency between different batches of tea caused by open-loop control in existing technologies, ensuring the system has high stability and good product quality consistency.

[0184] Furthermore, in this embodiment, through the cooperation of the temperature correction unit, moisture content correction unit, breakage rate deviation calculation unit, and coupling calculation unit of the multi-parameter coupling optimization module, the system can comprehensively consider the coupled influence of three key process parameters—breakage rate deviation, tea temperature, and tea moisture content—on the rolling pressure. It adopts a layered coupling strategy of "multiplication before addition" to generate optimized control parameters, which solves the problem in the prior art that it can only be controlled based on a single parameter (such as time or pressure) and ignores the influence of environmental factors such as temperature and moisture content. This ensures that the entire system has the control capability of multi-parameter collaborative optimization and strong environmental adaptability.

[0185] Example 2: This example should be understood as including all the features of any of the foregoing examples, and further improving upon them, according to... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 ,as well as Figure 6 As shown, the exudate conductivity detection module also includes a micro-negative pressure promoting unit, which is used to apply an adjustable negative pressure in the exudate collection area to accelerate the directional flow of exudate from the tea leaf layer to the collection and detection area and shorten the exudate response time. The micro-negative pressure value is adaptively adjusted by the multi-parameter coupling optimization module according to the breakage rate deviation: when the breakage rate deviation exceeds the first threshold, the negative pressure value is increased to accelerate the exudate detection; when the breakage rate deviation is within the target range, the negative pressure reference value is maintained; when the breakage rate deviation is negative, that is, the actual breakage rate exceeds the target, the negative pressure value is decreased to slow down the breakage rate.

[0186] The micro-negative pressure promoting unit accelerates the directional flow of exudate from the tea layer to the collection and detection area by applying adjustable negative pressure in the exudate collection channel 18, thereby shortening the exudate response time and improving the real-time performance of the system.

[0187] The micro-negative pressure promoting unit includes a vacuum pump 26, a negative pressure regulating valve, a negative pressure pipeline 15, and a pressure sensor 27. The vacuum pump 26 serves as the negative pressure source and can be either a rotary vane vacuum pump 26 or a diaphragm vacuum pump 26.

[0188] This embodiment uses a diaphragm vacuum pump 26, which has the advantages of being oil-free, low-noise, and maintenance-free, making it suitable for food processing environments. A negative pressure regulating valve is installed between the vacuum pump 26 and the negative pressure pipeline 15 to regulate the magnitude of the negative pressure. This embodiment uses an electric proportional regulating valve or a solenoid regulating valve to continuously adjust the negative pressure value within the range of -50 to -200 Pascals by controlling the valve opening. The regulating valve receives control signals (0~10V analog signals or PWM signals) output from the control processor and automatically adjusts the valve opening.

[0189] Negative pressure pipeline 15 guides the negative pressure generated by vacuum pump 26 to each collection channel. In this embodiment, the three collection channels (central area 28, middle area 29, and edge area 30) are connected to vacuum pump 26 through independent negative pressure pipelines 15. Each pipeline is equipped with an independent negative pressure regulating valve, which can realize independent control of each zone (a simplified scheme can also be adopted, that is, using a single negative pressure source to control the three areas uniformly). The negative pressure pipeline 15 is made of negative pressure resistant silicone hose or stainless steel pipe.

[0190] In addition, pressure sensor 27 is installed on the collection channel or negative pressure pipeline 15 to monitor the negative pressure value in real time. The pressure sensor 27 adopts a negative pressure type pressure transmitter and transmits pressure data to the control processor via RS485 or analog signal (4~20mA).

[0191] During normal kneading, the exudate seeps downwards from the tea leaf layer under the influence of gravity, flows through the micropores on the surface of the kneading disc 1, and enters the collection channel. Due to the certain thickness (usually 10 to 20 cm) and porosity of the tea leaf layer, the seepage rate of the exudate is relatively slow. There is a response delay of 5 to 8 minutes from the time the tea leaf cells are damaged to the time the exudate reaches the collection channel and is detected by the conductivity sensor 19.

[0192] When a slight negative pressure (-50 to -200 Pascals) is applied within the collection channel, the air pressure inside the collection channel is lower than that inside the tea leaf layer, creating a pressure gradient. Driven by this pressure gradient, the flow rate of the exudate from the tea leaf layer to the collection channel increases, and the response delay is shortened to 2 to 3 minutes, improving the real-time performance of conductivity detection.

[0193] In this embodiment, the negative pressure value needs to be selected appropriately. Too low a negative pressure (e.g., -20 to -30 Pascals) will not have a significant promoting effect; too high a negative pressure (e.g., -300 to -500 Pascals) may cause air channels to form within the tea leaf layer, allowing air to flow preferentially, which would negatively affect the stable collection of the exudate. In this embodiment, the negative pressure adjustment range is set to -50 to -200 Pascals, balancing the promoting effect and collection stability.

[0194] When the micro-negative pressure promoting unit is activated, the system presets a negative pressure reference value as the negative pressure operating point under normal working conditions. In this embodiment, the negative pressure reference value is set to -100 Pascals. This reference value is written to the negative pressure regulating valve by the control processor at the start of kneading, so that the negative pressure in the collection channel is stabilized at around -100 Pascals.

[0195] Besides accelerating exudate collection, the micro-negative pressure also has a slight impact on the tea leaf breakage process. The application of negative pressure creates a slight downward pull within the tea leaf layer, assisting the rolling pressure in its effect. As the negative pressure increases, this auxiliary effect strengthens, promoting cell breakage to some extent; as the negative pressure decreases, the auxiliary effect weakens, and the breakage rate slows slightly. Based on this characteristic, this embodiment uses the micro-negative pressure value as an auxiliary adjustment variable of the system, adaptively adjusted by the multi-parameter coupling optimization module according to the breakage rate deviation, achieving refined control of the breakage process. For details of the specific adjustment strategy, please refer to the description of the multi-parameter coupling optimization module.

[0196] The design of the micro-negative pressure promoting unit not only improves the response speed of conductivity detection, but also adds an adjustable control dimension, further enhancing the adaptive control capability of the kneading process.

[0197] In addition, the coupled calculation unit generates a micro-negative pressure control value P_vac based on the breakage rate deviation, realizing adaptive adjustment of the micro-negative pressure. The adjustment of the micro-negative pressure has a dual purpose: firstly, it changes the exudate collection rate by adjusting the magnitude of the negative pressure, thereby accelerating the detection response when the breakage rate deviation is large; secondly, it utilizes the auxiliary effect of negative pressure on the breakage process, combined with the kneading pressure, for fine adjustment.

[0198] 1) When the breakage rate deviation exceeds the first threshold (insufficient breakage), that is, when the breakage rate deviation ΔD is greater than the first threshold ΔD_th1, it indicates that the current breakage rate is significantly lower than the target value, and the breakage is insufficient. In this embodiment, the first threshold ΔD_th1 is set to 5%, that is, when ΔD > 5%, this control strategy is triggered.

[0199] At this point, the coupled calculation unit generates a larger micro-negative pressure control value, increasing the negative pressure within the collection channel. The specific calculation formula is as follows: ;

[0200] Where: P_vac is the output micro negative pressure control value, in Pascals (Pa), and the value is negative (e.g., -150 Pa); P_vac0 is the negative pressure reference value, which is -100 Pa in this embodiment; ΔP_vac is the negative pressure increment, calculated using the following formula: Kvac is the negative pressure adjustment coefficient, which is set to 5 Pa / % in this embodiment.

[0201] 2) When the breakage rate deviation is within the target range, i.e., -ΔD_th2 ≤ ΔD ≤ ΔD_th1, it indicates that the current breakage rate is close to the target value and the degree of breakage is appropriate. In this embodiment, the second threshold ΔD_th2 is set to 3%, i.e., when -3% ≤ ΔD ≤ 5%, it is considered to be within the target range.

[0202] At this point, the micro-negative pressure control value generated by the coupled calculation unit is equal to the negative pressure reference value: This maintains the negative pressure baseline, ensuring the stability of exudate collection and the continuity of detection.

[0203] 3) When the breakage rate deviation is negative (excessive breakage), if the breakage rate deviation ΔD < -ΔD_th2, i.e., ΔD < -3%, it indicates that the actual breakage rate exceeds the target value, indicating excessive breakage. In this case, the coupled calculation unit generates a smaller micro-negative pressure control value to reduce the negative pressure in the collection channel. The specific calculation formula is as follows:

[0204] ;in: ;

[0205] In this embodiment, to ensure the safe operation and collection effect of the micro-negative pressure promoting unit, the coupling calculation unit sets a limit range for the micro-negative pressure control value P_vac: 200 Pa ≤ P_vac ≤ -50 Pa;

[0206] If the calculated P_vac exceeds this range, then the boundary value is taken.

[0207] The lower limit of negative pressure is -200 Pa to ensure that the negative pressure is not too high and causes air channels to form in the tea leaves; the upper limit of negative pressure is -50 Pa to ensure that the negative pressure is not too low and loses its promoting effect.

[0208] At the end of each calculation cycle (30 seconds), the coupled calculation unit transmits the calculated micro-negative pressure control value P_vac to the central processing unit of the negative pressure regulating valve in the micro-negative pressure promoting unit via an RS485 communication bus or an analog signal output (0-10V, corresponding to -200 to 0 Pa). The central processing unit adjusts the opening of the negative pressure regulating valve according to the received control value, so that the actual negative pressure in the collection channel follows the change in the control value.

[0209] Through adaptive adjustment of micro-negative pressure, the system achieves more refined breakage rate control. When breakage is insufficient, it not only directly promotes breakage by increasing the kneading pressure, but also accelerates the detection response and assists in breakage by increasing the negative pressure, thus quickly correcting deviations through multiple measures. When breakage is excessive, it not only inhibits breakage by reducing the kneading pressure, but also slows down the breakage rate by reducing the negative pressure, preventing the breakage rate from further deteriorating. Micro-negative pressure adjustment, as an auxiliary control method, works synergistically with kneading pressure control to improve the system's control flexibility and accuracy.

[0210] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of protection of the present invention. Therefore, all equivalent technical changes made based on the content of the present invention specification and drawings are included within the scope of protection of the present invention. Furthermore, the elements therein can be updated as technology develops.

Claims

1. A dynamic control system for tea rolling based on multi-parameter coupling optimization, characterized in that, It includes an exudate conductivity detection module, a cell disruption rate identification module, a multi-parameter coupling optimization module, and an adaptive control execution module. The exudate conductivity detection module detects the conductivity of the tea exudate in real time during the kneading process. The cell breakage rate identification module identifies the current cell breakage rate of the tea based on the conductivity value detected by the exudate conductivity detection module; the multi-parameter coupling optimization module generates optimized rolling control parameters based on the breakage rate identified by the cell breakage rate identification module, combined with the tea temperature and moisture content. The adaptive control execution module receives the control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the actual working parameters of the kneading machine. The multi-parameter coupling optimization module includes a breakage rate deviation calculation unit, a temperature correction unit, a moisture content correction unit, and a coupling calculation unit. The breakage rate deviation calculation unit calculates the deviation between the current cell breakage rate identified by the cell breakage rate identification module and the preset target breakage rate. The temperature correction unit generates a temperature correction parameter based on the current tea temperature. The moisture content correction unit generates a moisture content correction parameter based on the current tea moisture content. The coupling calculation unit generates rolling control parameters based on the deviation value calculated by the breakage rate deviation calculation unit, the temperature correction parameter generated by the temperature correction unit, and the moisture content correction parameter generated by the moisture content correction unit.

2. The dynamic control system for tea rolling based on multi-parameter coupling optimization according to claim 1, characterized in that, The exudate conductivity detection module includes a layered detection structure, which divides the collection space at the bottom of the kneading disc into multiple independent collection areas along the radial direction. Each area is equipped with an independent exudate collection channel and conductivity detection unit.

3. The dynamic control system for tea rolling based on multi-parameter coupling optimization according to claim 2, characterized in that, The layered detection structure divides the bottom of the kneading disc radially from the center outward into three independent collection areas: the central area, the middle area, and the edge area.

4. The tea leaf rolling dynamic control system based on multi-parameter coupling optimization according to claim 3, characterized in that, The cell damage rate identification module identifies the damage rate by establishing a quantitative mapping relationship between the exudate conductivity and the cell damage rate, and calculates the difference between the measured conductivity and the benchmark conductivity calibrated before kneading. Combined with the preset conductivity-damage rate conversion coefficient, the cell damage rate of the current tea leaves is obtained by inversion.

5. The dynamic control system for tea rolling based on multi-parameter coupling optimization according to claim 2 or 4, characterized in that, The adaptive control execution module includes a pressure adjustment unit, a speed adjustment unit, and a temperature adjustment unit. The pressure adjustment unit receives the kneading pressure control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the pressurizing device of the kneading machine to change the kneading pressure applied to the tea leaves. The speed adjustment unit receives the kneading speed control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the rotation speed of the kneading drum to change the dynamic intensity of kneading. The temperature adjustment unit receives the kneading temperature control parameters generated by the multi-parameter coupling optimization module and adaptively adjusts the temperature of the kneading environment to maintain or change the temperature of the tea leaves. The actual working parameters of kneading include at least one of kneading pressure, kneading speed, and kneading temperature.

6. The dynamic control system for tea rolling based on multi-parameter coupling optimization according to claim 5, characterized in that, The coupling calculation unit generates the kneading control parameters in the following manner: the preset benchmark kneading pressure is coupled with the temperature correction parameter in a first coupling operation, and then coupled with the moisture content correction parameter in a second coupling operation to obtain the corrected benchmark pressure. The corrected benchmark pressure is then adjusted by the deviation value calculated by the breakage rate deviation calculation unit to generate a real-time kneading pressure control value as the kneading control parameter.

7. The dynamic control system for tea rolling based on multi-parameter coupling optimization according to claim 1 or 6, characterized in that, The moisture content correction parameter is determined in segments according to the moisture content range of the tea leaves: when the moisture content of the tea leaves is within the first moisture content range, it is determined as the first correction coefficient; when the moisture content of the tea leaves is lower than the first moisture content range, it is determined as the second correction coefficient, which is less than the first correction coefficient, in order to reduce the rolling pressure and prevent excessive damage to the tea leaves; when the moisture content of the tea leaves is higher than the first moisture content range, it is determined as the third correction coefficient, which is greater than the first correction coefficient, in order to increase the rolling pressure and overcome the problem of cells not being easily damaged due to high moisture content.

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